What Is Meant By "subsistence Farming?

The term "subsistence Farming" refers to a type of farming where only enough food is produced to feed the family working it.  

This method of farming normally requires a plot of land that is between 1000 and 40,000 square metres per person.  

It can be a harsh way of farming that provides little or no scope for improvement and hardly ever produces a surplus.  Even in the case where a surplus does occur, it may not be able to be sold as the farmer may not have clear title to the land or the crops they produce.

Subsistence farming is quite often done organically, although it's not necessarily always good for the environment.  There are various adverse impacts of subsistence agriculture on biological resources due to various bad agricultural practices.  One such bad practice is that of shifting cultivation where farmers will abandon a plot of land when its fertility gets too low and move on to more fertile land.  Many countries have acknowledged the adverse effects that this and other subsistence farming practices have on the environment.

Farming that provides enough food for the family